Apparatus for the automatic folding and creasing of sheet material

ABSTRACT

This invention relates to an apparatus for folding and creasing a sheet of material, comprising rotatable drum means for receiving said sheet on its periphery, A PAIR OF DRIVABLE NIP ROLLERS ON AXES PARALLEL TO THE DRUM AXIS, FOR FEEDING THE SHEET ONTO THE DRUM WHILE THE LATTER IS BEING ROTATED, SAID ROLLERS BEING PIVOTAL PARALLEL TO THEIR AXES TO BRING EACH, ONE AT A TIME, INTO DRIVING CONTACT WITH THE DRUM, A SCANNING ELEMENT FOR THE LEADING EDGE OF THE MATERIAL ON THE DRUM MEANS, AND CONTROL MEANS, ACTUATED BY SAID SCANNING ELEMENT, TO STOP THE DRUM, SO TO PIVOT THE FEED ROLLERS THAT ONE OF THEM WHOSE SURFACE ADJACENT THE DRUM HAS BEEN ROTATING IN THE OPPOSITE DIRECTION TO THE DRUM NOW MAKES DRIVING CONTACT WITH THE DRUM TO DRIVE IT IN THE SAID OPPOSITE DIRECTION, WHEREBY THE MATERIAL IS FOLDED AND PASSES FOR CREASING BETWEEN THE DRIVING FEED ROLLER AND THE DRUM MEANS, AND THEN SO TO PIVOT THE FEED ROLLERS THAT THE OTHER OF THEM DRIVES THE DRUM IN ITS ORIGINAL DIRECTION WHEREBY THE MATERIAL IS AGAIN FOLDED AND PASSES FOR FURTHER CREASING BETWEEN THE NOW DRIVING FEED ROLLER AND THE DRUM.

limited States atent 1 1.

Heist et a1 a,sn9,sa7

May 7, 1974 [75] Inventors: Hans Heist, Wiesbaden-Schierstein; Dieter Silbereisen, Wiesbaden, both of Germany [73] Assignee: Kalle Aktiengesellschaft,

Wiesbaden-Biebrich, Germany [22] Filed: Apr. 20, 1 972 [21] Appl. No.: 245,922

[30] Foreign Application Priority Data Apr, 22, 1971 Germany 21 19372 t [52] US. Cl. 270/79, 270/73 [51] Int. CL; B65h 45/20 [58] Field of Search 270/30, 31, 39, 40, 61 F,

[56] References Cited UNITED STATES PATENTS 7 3,241 ,829 3/1966 Acher 270/61 R 3,712,610 1/1973 Garrone 270/79 2,854,233 9/1958 Groeper 1 270/79 3,697,062 10/1972 Mones et a1. 270/79 X 3,363,896 1/1968 McKindary 270/79 X 3,466,027 9/1969 Kwk, Jr 270/68 R X 2.947.536 Martin 270/79 Primary Examiner-Robert W. Michell Assistant ExaminerL. R. Oremland Attorney, Agent, or Firm-James 13. Bryan, Esq.

[5 7 ABSTRACT This invention relates to an apparatus for folding and creasing a sheet of material, comprising rotatable drum means for receiving said sheet on its periphery,

a pair of drivable nip rollers on axes parallel to the drum axis, for feeding the sheet onto the drum while. the latter is being rotated, said rollers being pivotal parallel to their axes to bring each, one at a time, into driving contact with the drum,

a scanning element for the leading edge of the material on the drum means,

and control means, actuated by said scanning element, to stop the drum, so to pivot the feed rollers that one of them whose surface adjacent the drum has been rotating in the opposite direction to the drum now makes driving contact with the drum to drive it in the said opposite direction, whereby the material is folded and passes for creasing between the driving feed roller and the drum means, and then so to pivot the 7 feed rollers that the other of them drives the drum in its original direction whereby 'the material is again folded and passes for further creasing between the now driving feed roller and the drum.

10 Claims, 6 Drawing Figures PATENIED 1 IBM 3.809.387

APPA 'IUS FOR THE AUTOMATIC FOLDING AND CREASING F SHEET This invention relates to an apparatus for the automatic folding and creasing of sheet material, whereby the material can be provided with a plurality of sharpedged parallel creases at any required intervalsQ In the case of a number of knowntypes of folding apparatuses (see, for example, German Pat. Nos. 1,61 1,375 and 1,804,084, as laid open), the material is passed between two rollers which rotate in opposite directions and which have contoured fold-forming portions at certain distances apart. However, such apparatus permits creases to be formed in a material only at particular constant intervals. In order to obtain a greater distance between creases in the material, for example, an apparatus of the same construction and having rollers of greater diameter is necessary. Nor is it generally possible with such apparatus to form creases in the material at irregular intervals; i.e. standard folding in accordance with German Standard Specification DIN 824 for instance, is not possible.

In other known apparatus, two push-pull levers carrying feed strips are used for forming the folds, these feed strips intermittently drawing the material into the apparatus at time intervals determined by the required distance between creases, and clamping the material in the extreme lever positions, so that a crease is formed. Creases located at constant distances apart are ob tained with such apparatus. Although it is possible to\ form creases at differing intervals in different sheets, it is not, however, possible to form creases at irregular intervals in a sheet,.using one and the same apparatus.

Also known are folding apparatuses whereby it is possible to form creases in a sheet at irregular intervals. However, because ofthe particular arrangement of the feed and fold-forming rollers, the sequence of intervals between the creases cannot be varied in one machine, so that one apparatus would be necessary for each size of sheet in order toachieve standard folding, e.g. in accordance with Specification DIN 824. German Standard Specification DIN 824 is disclosed in U.S. Pat. No. 3,241,829, particularly in' FIGS. 1 to 3 and columns 2 and 3 thereof.

The presentinvention provides an apparatus for folding and creasing a sheet of material, the apparatus including a rotatable drum for receiving the sheet on its periphery, a pair of drivable nip rollers on axes parallel to the drum axis, for feeding the sheet onto the drum while the latter is being rotated, the rollers being pivotal parallel to their axes to bring each, one at a time, into driving contact with the drum, a scanning element for the leading edge of the material on the drum and control means, actuated by the scanning element, to stop the drum, so to pivot the feed rollers that one of them whose surface adjacent the drum has been-rotating in the opposite direction to the drum now makes driving contact with the drum to drive it in the opposite direction, whereby the material is folded and passes for creasing between the driving feed roller and the .drum, and then so to pivot thefeed rollers that the other of them drives the drum in its original direction whereby thematerial is again folded and passes for further creasing between the now driving feed roller and the drum.

This apparatus enables creases to. be formed at variable intervals along the sheet and renders it possible to v '2 obtain standard folds in accordance with Specification DIN 824, for instance, in sheets of different using one and the same machine.

' The apparatus is also suitable for forming creases at constant intervals.

The. pair of feed rollers may be pivoted on an axis which is located midway between the axes of rotation of the rollers. By their pivoting movement, the two feed rollers alternatively are brought into driving contact with the drum. Since the two rollers rotate in opposite directions, their alternate movement into contact with the drum results in reversal of the direction in which the drum rotates. Each time the direction of rotation is changed, a crease is formed in the material, since the part of parts of the material already on the drum and the part passing through the pair of feed rollers are both or all overridden by the driving feed roller.

The scanning element disposed in the path of travel of the material may be a mechanical switch, e.g. a micro-switch, or a photo-electric switch, e.g. a photoelectric cell. The scanning element is preferably so disposed in the path of travel of the material that it is actuated by the forward edge of the material when the first fold is to be formed. If the scanning-element is so arranged that it is actuated at an earlier stage, a timedelay element must .be connected between the switching element and the control device. In the case of standard folds, e.g. in accordance with Specification DIN 824, the distance between the leading edge of the material and the first fold is the same for all sizes of material. In the case of non-standard folds formed at constant distances apart, the distance between the leading edge of the material and the first fold must be variable depending upon the particular constant interval between folds that is required. For such folding operations, use is preferably made of a'scanning element, theposition of which can be adjusted, or of a plurality of individually selectable scanning elements.

The control operation for pivoting the pair of feed rollers can be carried out mechanically or electromechanically. However, the control device preferably consists of electronic timing elements. Each timing element consists of a plurality of timing stages. The pair of feed rollers is pivoted at the commencement of each timing stage and, as described above, the material is provided with a new fold. The last timing stage determines the end of the folding and creasing operation. Each timing element is adapted for the forming of standard folds in one size of material, e.g. one timing element is used for forming folds in a DIN A0 sheet in accordance with Specification DIN 824. A DIN AO sheet is specifically disclosed in FIG. 1 of U.S. Pat. No. 3241.82 and a afqtmat t itx.1.1.89mm closed in column 2, lines 58 and 59 of the aforementioned U.S. patent. v

In the case of non-standard folding operations, i.e. the forming of creases at constant intervals in a piece of material of indeterminate length, the associated timing elements cannot comprise a specific last timing stage which terminates the folding operation, since it is not known where the material ends. However, in order to ensure that the folding operation is terminatd at the right moment, a further scanning element which responds to the passing of the trailing edge of the material is then arranged in the path of travel of the material. As soon as this scanning element is cleared by the trailing edge of the material, it acts upon the timing element sizes and the timing element.

Guide members, which extend over part of the periphery of the drum and which both guide the material on, and press it against, the drum, may be'fitted on each side of the pair of feed rollers; guide plates, guide strips, or rollers running over the drum may be used in known manner as the guide members.

When the material is introduced into the apparatus at the commencement of the folding operation, the pair of feed rollers may occupy either of two initial positions. In the first initial position, that guide roller rotating in thedirection to advance the leading edge of the material towards the scanning element is in contact with and drives the drum. In the other preferred initial position, the pair of guide rollers is slightly inclined to the horizontal, so that neither of them is in contact with the drum. During this time, the drum is driven by its own motor, advantageously at a greater peripheral speed than the feed rollers. The direction of rotation of the drum is so selectedthat the leading edge of the material is moved towards the scanning element. This initial position ensures that less trouble occurs in moving the material into the apparatus. When the scanning element is actuated by the leading edge of the material,

the drum motor is stopped, and the pair of feed rollers is pivoted into the position described, in which one of them isin contact with the drum and drives it.

A. guide track may be provided for the folded material discharged atone of the sides of the drum, the material slidingalong this track and into a receiving bin. A second guide track may be provided for folded materiaI discharged at theother side of the drum, this track being so disposed that the folded material falls off it onto the other guide track and from there slides into the receivingbin. This arrangement of guide tracks ensures that the folded material, irrespective of the direction of rotation of the drum, always runs into the receiving bin' in the same orientation at the end of the folding operation, e.g. with its labelling or markingfacing upwards. 4

The invention is diagrammatically illustrated by' way of example in the accompanying drawings, in which:

' FIG. 1 is a cross-section through the apparatus,

' FIG. 2 is a portion of FIG. 1 on a larger scale,

' FIG. 3 shows the position of material being folded, in various stages of the folding operation,

FIG. 4 is an end elevation of the apparatus correspondingto FIG. 1,

FIG. 5 is an end elevation of the apparatus from the opposite end, and

FIG. 6 is a block circuit diagram of the control means of the apparatus. v

Referring to the drawings, in FIG. 1 the housing of the apparatus is designated by the numeral 1. A sheet 2 for folding and creasing, with its labelling or marking (shown as a heavier line in the drawing) facing upwards and pointing'forwards, is passed over a feed table 3 and beneath a guide plate 4 and is inserted between two feed rollers 5 and 6 which carry it onto a drum 7. The path of travel of the sheet over the drum 7 is confined either by a guide roller 8 and a pressure roller 9 or by a guide roller 1,0 and a pressure roller 11, depending upon the direction in which the drum is rotating. After completion of the folding and creasing operations, the folded and creasedsheet 2, depending upon the dire- 4 tion in which the drum 7 is rotating when the last fold is formed, either passes over a guide track 12 into a receiving bin l3,"or slides over a guide track 14 on to the guide track 12 and from there into the receiving bin 13. Two photo-electric cells 15 and 16 are disposed in the path of travel of the sheet 2 and close photoelectric the downstream side of the pressure roller 9; these photoelectri cells respond to the presence of the leading edge of the sheet and are individually selectable depending upon the required distance between the leading edge of the sheet and the first fold. Located upstream of the two feed rollers 5 and 6 is a further photo-electric cell 17 which responds to the passing of the trailing edge of the sheet. The two feed rollers 5 and 6 are mounted in a support 18 (FIG. 2) and are driven at a constant peripheral speed by a motor 19 by way of a clutch 20, a chain 21, a sprocket 22 and gear wheels 23 and, 24 see FIG. 5). The two feed rollers 5 and 6 are held by a magnet 25in an initial position slightly inclined to the horizontal (see FIG. 4). When the magnet is de- 25 positions indicated by the numerals 5' and 6', the roller 6 is in contact with the drum 7 and drives it (see FIG. 5), whereas when the rollers are in the positions 5" and 6", the roller 5 drives the drum 7 (see FIG. 2).

FIG. 4 shows the initial position in which the magnet 25 is energized, the magnets 26 and 27 de-energized,

and switches S 29 and S 30 are both closed. During this time, in which neither of the rollers 5 or 6 is in contact with the drum 7, the latter is driven by a motor 31 by way of a chain 32, a sprocket 33 and a clutch 34. In the initial position, the pressure roller 9 is lifted from the drum 7. By energization of a magnet 35, the pressure roller 9 is moved into the position 9' about an axis 37 with the aid of a lever system 36 (see FIG. 5).

FIG. 6 shows a block circuit diagram for the initial position of the apparatus, i.e. when the apparatus is started up by means of a main switch S 38, but before the leading edge of the sheet 2 has reached the photoelectric cells 15 andl6. When the sheet 2 is fed in, one of a series of switches S 39a to S 39f is actuated by the machine operator and thus one of a series of timingelemerits 40a to 40f of a control means 40 is selected. When the sheet 2 is to be folded and creased in an standard manner, e.g. in accordance with German Standard Specification DIN 824, then, depending upon its shape, one of the timing elements 40a to 40d isselected. If however the sheet is to be folded and creased at regular intervals, one of the timing elements 402 or 4f is selected. In the case to be considered below, a constant distance between creases 190 mm), for which the timing element 40c is selected, corresponds to the distance between the leading edge of the material and the first crease in the formation of standard creases. Therefore, the timing element 40e as well as the timing elements 40a to 40d are set in operation by the photo-electric cell 15. The timing element 40f can be selected for a second constant distance between creases (2l0 mm), and is set-in operation by the photoelectric cell 16.

Each of the timing elements 40a to 40f comprises 1 to n timing stages. Each timing stage controls the next.

In the case of the timing elements 40a to 40d for forming standard creases, the last timing stage is predetermined in each case. In the case of timing elements 40e and 40f for non'standard creasing with constant distances between creases, and where the length of the sheet is unknown, the last timing stage is determined by the photo-electric cell 17. As soon as the photoelectric cell 17 is cleared by thetrailing end of the sheet, it

sends a pulse to the timing element 40e or 40f. This pulse causes the timing stage, operating up to the moment at which the pulse is sent, and also the next timing stage also operated by the aforementioned timing stage, to continue to be operative, but no further timing stage is actuated.

The last timing stage n of each timing element 40a to 40f actuates a wiping contact relay 41, which returns the apparatus to its initial position.

When, for example, a DIN A sheet is to be creased in accordance with Specification DIN 824, the switch S 39a is actuated by the operator. This selects the timing element 40a and brings the photo-electric cell 15 into action. The apparatus is in the initial position in which neither of the two feed rollers and 6 is in contact with the drum 7, and in which the pressureroller 9 is lifted from the drum 7. This position is shown in FIG. 2 in solid lines. As described above, the drum 7 is driven by its motor 31 in the direction indicated in FIG. 2 by the solid line arrow.

The sheet 2 fed into the apparatus over the feed-table 3 and beneath the guide plate 4 is seized by the two feed rollers 5 and 6 and passed onto the drum 7 which carries it under the guide roller 8 and the raised pressure roller 9 to the photo-electric cells and 16. The

' inserted part of the sheet 2 occupies the position shown in FIG. 3a. As soon as the leading edge of the sheet 2 actuates the photo-electric cell 15 primed by the switch S 39a, a relay 42 pulls up; this relay locks to its own contact and actuates associated switches S 42a to S 421. This causes the drum drive to be switched off, the two feed rollers 5 and 6 to be braked for a brief period, and the first timing stage of the timing element 40a, selected by the switch S 390 prior to the feed-in of the sheet 2, to be charged.

As this is happening, the following individual operations or movements take place: the switches S 42a to S 420 are opened and the motor 31 driving the drum 7 is thereby stopped, the clutch 34-for the drum 7 is disengaged, and the magnet 25 is de-energized. Since the switch 42d'is closed, the magnet 35 is energized and the pressure roller 9 is thus brought into the position 9'. The switch S 42e is closed and, since the switches S 29 and S 30 are also closed, a relay 43 pulls up so that a switch S 43 is lifted from a contact 44 and applied to a contact 45, i.e. a brake 46 for the feed rollers and a drum brake 47 are energized, and the feed-roller clutch 'is disengaged. Also, the switches S 42f to S 421 are closed, so that connections between the switches S 39a to S 39f on the one hand and the respective associated timing elements 40a to 40f on the other are established. However, only the first timing stage of the pre-selected timing element, in thiscase the first timing stage of the timing element 40a, is charged. The magnet 27 is energized by the first timing stage, so that the two feed rollers 5 and 6 are pivoted about the axis 28 into the positions 5' and 6', in which the roller 6 is in contact with the drum 7, and drives this in the direction indicated by the broken-line arrow. The guide rollers 8 and 10 and the pressure rollers 9 and 11- are driven by the drum 7 in the direction of the broken-line arrows (see FIG. 2). When the magnet 27 is fully energized, the switch S 29 is opened, so that the relay 43 drops and the switch S 43 is lifted from the contact 45 and applied to the contact 44, and as a result the feed-roller brake 46 and the drum brake 47 are released, and the feed-roller clutch 20 is engaged.

That part of the sheet 2 already on the drum 7 is at this time in the position shown in FIG. 3b and is likewise moved in the other direction by reversal of the rotation of the drum 7. This part of the sheet 2 and also the fresh part passing through the two feed rollers 5 and 6 are overridden by the roller 6 (see FIG. 3b), and the first crease is formed.

The first timing stage of the timing element 40a actuates the second timing stage-After the first timing stage has been completed, that part of the sheet 2 that is travelling over the drum 7 occupies the position shown in FIG. 3c. Upon commencement of the second timing stage, the magnet 27 is de-energized so that the switch S 29 is closed. At the same time the magnet 26 is energized..While the magnet '27 has not yet reached its terminal position, the switch S 30 remains closed. Since all three switches S 29, S '30 and S 42e remain closed for a brief period, the relay 43 is pulled up and the switch S 43 is moved from the contact 44 and applied to the contact 45, so that the feed-roller brake 46 and the drum brake 47 pull up, while the-feed-roller I clutch 20 is disengaged. When the magnet 26 is fully energized, it opens the switch S 30 so that the relay 43 drops and the switch S 43 again moves on to the contact 44. The brakes 46 and 47 are thus released again and the clutch 20 is engaged. By energization of the magnet 26, the two feed rollers 5 and 6 pivot into the positions 5" and 6" in which the roller 5 drives the drum 7 .in the direction indicated by the solid-line arrow. The sheet 2 occupies the position shown in FIG. 3d and the second crease is formed.

This train of events is repeated at the commencement of each subsequent timing stage. The last timing stage n actuates the wiping contact relay 41 so that the selflocking contact of the relay 42 is lifted and the switches S 42a to S 421 are moved into the initial position shown in FIG. 6, i.e. the two feed rollers 5 and 6 return to their initial positions, the motor 31 drives the drum 7, and the pressure roller 9 is lifted from the drum 7. In the meantime the folded and creased sheet 2' slides into the receiving bin 13 as described above.

When a sheet 2 is to be creased at constant intervals of 210 mm, the same train of events as that just described takes place with the exception that the switch S 39f is used and thus the timing element 40f and photo-electric cell 16 are selected. The movements for forming the first crease are thus initiated only when the leading edge of the sheet actuates the photo-electric cell 16. A further difference as compared with the above-described cycle of operations is that the last timing stage n is not fixed beforehand but is determined by the photo-electric cell 17 when this is cleared by the trailing edge of the sheet.

It will be obvious to those skilled in the art that many modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

What is claimed is:

1. An apparatus for folding and creasing a sheet of ing said sheet on its periphery,

, 7 a pair of drivable nip rollers on axes parallel to the drum-axis, for feeding the sheet onto the drum .while the latter is being rotated, said rollers being pivotal parallel 'to their axes to bring each, one at a time, into driving contact with the drum, a scanning element for the leading edge of the material on the drum means, and control means, actuated by said scanning element, to stop the drum, and to pivot the feed rollers so that one of themwhose surface adjacent the drum has been rotating in the opposite direction to the drum now makes driving contact with the drum to drive it in the said opposite direction, whereby the material is folded and passes for creasing between the driving feed roller and the drum means, and then to pivot the feed rollers so that the other of them drives. the drum in its original direction whereby the material is again folded and passes for further creasing between the now driving feed roller and the drum. 2. An apparatus as claimed in claim 1 including separate driving means for the initial rotation of the drum when the sheet is fed onto it.

3. An apparatus as claimed in claim 1, in which the said control means comprises at least one electronic timing element.

4. An apparatus as claimed in claim 1, in which guide elements for the material are disposed adjacent the pe-' 8' riphery of the drum on both sides of the feed point of the material onto the drum.

5. An apparatus as claimed in claim 4, in which the said guide elements are rollers which run on the drum.

6. An apparatus as claimed in claim 1, including means for changing the position of the said scanning element to vary the position of the first fold.

7. An apparatus as claimed in claim 1, including, at different distances from the nip of the feed rollers, at least two individually selectable scanning elements'for the leading edge of the material on the drum.

8. An apparatus as claimed in claim 1, including a further scanning element for the trailing edge of the material, for stopping the control means.

9. An' apparatus as claimed in claim 1, including means for discharging folded and creased sheets from both sides of the drum and for conveying discharged sheets to a single receiving bin, the arrangement being such that from whichever side of the drum the sheet is discharged, it arrives in the bin in the same orientation.

own motor when the rollers are in this position. 

1. An apparatus for folding and creasing a sheet of material, comprising rotatable drum means for receiving said sheet on its periphery, a pair of drivable nip rollers on axes parallel to the drum axis, for feeding the sheet onto the drum while the latter is being rotated, said rollers being pivotal parallel to their axes to bring each, one at a time, into driving contact with the drum, a scanning element for the leading edge of the material on the drum means, and control means, actuated by said scanning element, to stop the drum, and to pivot the feed rollers so that one of them whose surface adjacent the drum has been rotating in the opposite direction to the drum now makes driving contact with the drum to drive it in the said opposite direction, whereby the material is folded and passes for creasing between the driving feed roller and the drum means, and then to pivot the feed rollers so that the other of them drives the drum in its original direction whereby the material is again folded and passes for further creasing between the now driving feed roller and the drum.
 2. An apparatus as claimed in claim 1, including separate driving means for the initial rotation of the drum when the sheet is fed onto it.
 3. An apparatus as claimed in claim 1, in which the said control means comprises at least one electronic timing element.
 4. An apparatus as claimed in claim 1, in which guide elements for the material are disposed adjacent the periphery of the drum on both sides of the feed point of the material onto the drum.
 5. An apparatus as claimed in claim 4, in which the said guide elements are rollers which run on the drum.
 6. An apparatus as claimed in claim 1, including means for changing the position of the said scanning element to vary the position of the first fold.
 7. An apparatus as claimed in claim 1, including, at different distances from the nip of the feed rollers, at least two individually selectable scanning elements for the leading edge of the material on the drum.
 8. An apparatus as claimed in claim 1, including a further scanning element for the trailing edge of the material, for stopping the control means.
 9. An apparatus as claimed in claim 1, including means for discharging folded and creased sheets from both sides of the drum and for conveying discharged sheets to a single receiving bin, the arrangement being such that from whichever side of the drum the sheet is discharged, it arrives in the bin in the same orientation.
 10. An apparatus as claimed in claim 1 in which the said drivable feed rollers are capable of being pivoted into a position in which none of them is in driving contact with the drum, and the drum is driven by its own motor when the rollers are in this position. 